Abstract: A zoom lens system includes: a first lens group having positive power; a second lens group having negative power; a third lens group having positive power; a fourth lens group having positive power; a fifth lens group having negative power; and a following lens group following the fifth lens group. The first to fifth lens groups and the following lens group are arranged in this order such that the first lens group is located closest to an object and that the following lens group is located closest to an image. While the zoom lens system is zooming, intervals between the respective lens groups change. While the zoom lens system is focusing from an infinity focus point through a shortest shooting range, a plurality of negative lens groups included in the fifth lens group and the following lens group move.

Abstract: A fixing device includes a heat roller, which is rotatably mounted to a frame, a press roller, which is rotatably mounted to the frame, and a press mechanism for pressing the press roller against the heat roller. The press mechanism has a displacement member that is displaceable in a press direction, a bearing portion that is movable in the opposite direction relative to the displacement member and supports the press roller at a shaft portion thereof, an urging member for urging the bearing portion in the press direction, and displacing structure for displacing the displacement member between a first position corresponding to a non-press position and a second position corresponding to a press position. The urging force of the urging member in the press direction is reinforced by action of the bearing portion, which is displaced in the opposite direction relative to the displacement member when the displacement member is displaced from the first position to the second position.

Abstract: A plastic coupling for plastic tubing having a groove annulus formed between a first circumferential groove on the outer periphery of the enlarged diameter portion of a connection tube and a second circumferential groove on the inner periphery of a cap nut 5 when the cap nut 5 is mounted on a joint body, and an enlargeable split ring having an internal diameter smaller than the external diameter of the enlarged diameter portion and loosely fitted into the second groove, the split ring being adapted to slide on the enlarged diameter portion to the first groove until the split ring falls within the first groove and is located within the groove annulus when the cap nut is mounted on the joint body.

Abstract: In a pressure developing device employed in an imaging device like a duplicating machine, an optical printer etc., pressure force for evenly pressurizing a recording medium is capable of being varied in accordance with the width of the recording medium to be pressurized.

Abstract: In a pressure developing device employed in an imaging device like a duplicating machine, an optical printer etc, pressure force for pressurizing a recording medium is capable of being varied in accordance with the width of the recording medium to be pressurized.A sensor for detecting the width of the recording medium is provided, and the pressure force is varied based upon the detected value.

Abstract: A bellows pump which is disclosed herein has two bellows made of a plastic material and provided with liquid inlet and outlet ports for transferring a liquid by expanding and contracting the bellows. The bellows pump comprises cylinder cases in each of which the bellows is vertically expandably and contractably contained and mounted at its access port side to a ceiling of said cylinder cases, gas pumping means for alternately feeding a compressed gas from a lower end thereof into the cylinder cases, a pair of rods passed through bottoms of the cylinder cases and fixed to the lower ends of the bellows, and adapted to be moved in response to the expansion and contraction of the bellows, and actuating means adapted to be operated in response to the up and down movement of the rods.